1. Field of the Invention
This invention relates to the sport of archery and more particularly to devices and accessories which are used to hold and to release the bowstring.
2. Description of the Prior Art
In the usual manual shooting of a bow and arrow, the bowstring and the arrow are pulled back by the ends of the fingers of one hand of the archer, an operation that requires considerable muscular strength in the archer's fingers. The difficulty encountered in holding the bowstring often results in erratic release of the string by the archer, and a resultant loss of accuracy.
Various devices have been developed which allow the archer to pull back the bowstring by pulling on a bowstring release device with the ends of the fingers of the hand. Depending on the device, the release of the bowstring may be accomplished by pulling a trigger which is provided on the device, or by releasing the trigger. U.S. Pat. No. 4,170,216 to Wilson discloses a bowstring release mechanism having a latching cam which holds the bowstring, and a trigger cam which prevents the latching cam from rotating to release the bowstring until the trigger cam is rotated by the archer's moving the trigger cam by pressing the trigger arm. A bowstring trigger release mechanism having a latching cam, actuator cam, and a plunger which is used to press against and rotate the actuator cam to thereby release the latching cam and bowstring is disclosed in the U.S. Pat. No. 4,009,703 to Cunningham, Sr. Both the Wilson and Cunningham, Sr. bowstring release mechanisms allow for only an active release of the bowstring by the archer's pulling a trigger. U.S. Pat. No. 4,232,649 to Allen et al. discloses a bowstring trigger release which also incorporates a double-cam type mechanism requiring active release. However, the entire trigger actuating device must be in total engagement before the bowstring may be held by the device.
A passive bowstring release mechanism which utilizes a single cam having a lever which is restrained by the hand of the archer when the bowstring is held in the latching portion of the cam is disclosed in U.S. Pat. No. 4,424,791 to Muehleisen. Since the Muehleisen device has only a single cam, the entire force of pulling on the bowstring must be provided by the ends of the fingers of the hand. U.S. Pat. No. 4,539,968 to Garvison discloses a bowstring release device with a double-cam mechanism which operates so that the bowstring may be released either passively by the archer releasing the trigger, or actively by the archer pulling the trigger. The Garvison device has a trigger cam and a latch cam which have complimentary detents which engage to hold the latch cam in its bowstring-engaging position. When the Garvison bowstring release device is used in its passive release mode, a spring moves the trigger cam so that the latch cam is snapped from a detent in the trigger cam when the archer releases the trigger cam. When used in its active release mode, the archer moves the trigger cam so that the latch cam is snapped from a detent in the trigger cam.